The effect of reinforcing particles on the erosive wear behavior of particles reinforced silicone matrix composite coating

The effects of SiC and Al2O3 particle reinforcement on the erosive wear beh avior of silicone matrix composite coatings (SMCCs) were investigated using a gas blast rig. The optimal erosion resistance was reached through varyin g the type of reinforcing particle, reinforcing particle size and percentag e in the coating. It was found that the erosive wear behaviors of the three sizes of alpha -Al2O3 and SiC filled SMCC are different from each other th ough the optimal erosion resistance points occurred at nearly the same rein forcing particle weight percent. A plastic-brittle erosion behaviors transi tion occurred with the influence of reinforcing particle size. The experime ntal results show that coating hardness has an important influence on the S MCCs wear behavior. The maximum pencil hardness corresponds with the best e rosive wear resistance of SMCC. SEM pictures of the worn surface morphology indicate that the main erosive wear mechanisms of SMCC are microploughing and microcutting when impacted at 30 degrees impingement angle, whereas the erosion mechanisms at normal impact are mainly fatigue failure, caused by plastic deformation and microcracking. (C) 2001 Elsevier Science B.V All ri ghts reserved.